<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        div {
            width: 180px;
            height: 180px;
            border: 10px solid red ;
            margin: 0 auto;
        }
        .one{
            margin-bottom: 10px;
        }
    </style>
</head>
<body>
    <!-- <div class="one">1</div> -->
    <div>2</div>
</body>
</html>